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    <title>Title</title>

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        <th  colspan="2">星期一 星期二</th>

        <th>星期三</th>
        <th>星期四</th>
        <th>星期五</th>

    </tr>

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        <td rowspan="3">HTML  CSS基础</td>
        <td>HTML  CSS基础</td>
        <td>HTML  CSS基础</td>
        <td>HTML  CSS基础</td>
        <td>HTML  CSS基础</td>

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    <tr>

        <td>HTML  CSS基础</td>
        <td>HTML  CSS基础</td>
        <td>HTML  CSS基础</td>
        <td>HTML  CSS基础</td>
       

    </tr>

    <tr>

        <td>HTML  CSS基础</td>
        <td>HTML  CSS基础</td>
        <td>HTML  CSS基础</td>
        <td>HTML  CSS基础</td>

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